electrical problem?

[FAT TONY]

Alright so i drove to school one day and forgot to turn off the light. so for about six hours the light were on and drained the battery

I got a boost from a friend and was able to make it home but when i made it home i noticed my voltage was low on the gauge it was putting out about ten volts, so i decided to turn the truck off and turn it back on but when i did that the battery was to low to restart the truck. figured it was the alternator so i went to have it checked and it passed so then i figured voltage regulator but when i got a new one it didnt fix the problem. so now im kind of clueless as to what it could be.

when the truck is running i disconnect the ground wire and it turns off so i know its something in the alternator but what could it be?, the people at the auto parts store tested it about four times on the machine and it passed all four times, so if any one could help me out here it would be appreciated

[gofastnut]

I'd say you're battery is still low. Charge it first, just running the engine won't charge the battery. Also, you can cook an alternator trying to use it to charge your dead/low battery, or blow out your alternator by disconnecting the ground wire. I know on computer controlled vehicles, that's a big no-no, due to the potential for a voltage spike resulting in fried electronics.
Good luck.

[FAT TONY]

well i charged it for about an hour on fast charge and it worked pretty good for a while but then the battery got low and the truck just turned off, do you think my alternator might be bad? maybe the brushes in it or something?, and yea i learned that when i hooked the ground back up, it popped one of my fuses

[tincan1966]

Have you checked the voltage at the battery with the truck running? At about 1200-1500 engine RPM you should have a minimum of 13.7 yolts to around 14.5 at the battery. The older style w/external regulator will charge a bit lower than the later internally regultaed type.
A normal operating system should charge a battery and maintain it's charge.
it is also possible that your battery could be weak or have a shorted cell. If possible, have the batery fully charged and have it load tested. A battery cannot be tested without being fully charged.

Hope that is helpful

[FAT TONY]

thanks... ill go hook up the battery right now and let it charge for a while, could it be that when i got the jump start it might have fried something?

[63burban4x4]

Tony,
just be sure that your terminal ends on your battery cables are really clean....you'd be surprised how often this will keep a battery from charging well. Just putting the jumper clamps can loosen the terminal ends. You might want to replace them if they are not in good shape, or don't seem to tighten up well. Just another thought. Also, sometimes I have found that a battery that becomes really discharged to the point of being totally dead just never seems to be right again.

[66clow]

if the battery is kinda old and you drained it that low, you may have some bad cells in the battery. I agree with the above, especially if it the alternator was fine before it drained out.

[FAT TONY]

alright i cleaned the terminals and im charging it right now, its been about two hours, also when i took off the caps on the battery i noticed the acid in it was fairly low, but im not sure if it is like that, I am Running on an 18 wheeler battery so it might change from a regular car battery,

[63burban4x4]

If your battery liquid level is low, you don't need to add acid, just good clean water, distilled if possible. the higher the rate of your charger, the more likely you are to "boil" some of the water out of the battery. Some are sealed, and are not sevicable to refill. A slower charge at a lower rate for a longer tme is generaly better for the battery, I think. good luck

[markeb01]

I agree with everything that's been shared. It sounds like the battery, and indeed a slower charge at a low setting is better for the battery. Another thing to check is the condition of both battery cables. Make sure they don't have any cracks in the insulation and they are big enough to carry the voltage. If they need to be replaced ask for 6 volt cables at the parts store, they are twice as big. Also check to make sure the positive cable is tight at the starter. Having a loose cable either at the engine block or the starter can create all sorts of strange problems.

And distilled water is available at your local grocery store next to the drinking or spring water. Around here it's about 88 cents a gallon and your battery will last longer, compared to using tap water. Tap water introduces unwanted minerals into the battery which interfere with the chemical process.

There should be a ring near the top of each cell in the battery, below the bottom of the cap, that indicates the fill line.

[FAT TONY]

I charged it added water, didn't get a chance to buy distilled but hopefully it wont be to bad, I charged it and turned it on, the voltmeter said it was putting out about twelve volts but it still seemed pretty low, so i did the test to see if alternator was charging but it turned off, first it lasted about five seconds on but then it turned off, would the alternator brushes be considered a problem?

[Gianyveedub]

Check the voltage regulator and the ground to it and the alternator. I had a similar problem last week and it turned out that the new voltage regulator I bought was junk so I had to buy another one. To add to it, my grounds were not properly done. As some members on this forum have told me, grounds are one of the most important things to remember when dealing with electrical problems. Here is a link to my post and the resolution to my issues.

http://67-72chevytrucks.com/vboard/s...tage+regulator

Good Luck

[turbostar]

Also isn't there a polarize process that is req'd when installing a new regulator?

[luvbowties]

Originally Posted by turbostar

Also isn't there a polarize process that is req'd when installing a new regulator?

Not if using volt-reg with an alternator--only with use of generator.